Electric starting motor for power engines



March 10, 1925. 1,529,288

H. BAUMEISTER EZECTRIC STARTING MOTOR FOR POWER ENGINES Filed May 13, 1922 Inventor- 2 Heinrich Baum'eisterj His Attorney.

; Patented Mar. 10, 1 925.

HEINRICH BAUMEISTER, OF BEBLIN-PANKOW, GERMANY, ASSIGNOR TO GENERAL 'ELEormo comm, A. ooaromrrron or new YORK. I

ELECTRIC STARTING MOTOR FOB POWER ENGINES.

Application filed May 18, 1922. Serial No. 580;?75.

To all whom it may concern:

Be it known that I, Hammer: BAUMEIS- TER, a citizen of Germany, residing at Ber lin-Pankow, Germany, have invented cer- 5 tain new and useful Im rovements in Electric Starting Motors or Power Engines for which I have filed an application in ermany January 6 1920), of which the followin is a specification. I 10 This invention relates in general to a startin motor of the kind in which the motor an the wheel to be rotated by it are coupled with each other by means of a pin- 7 ion that is adapted to be slewed around the motor axle; in particular the invention relates to slewing the pinion by the rotary motion of the starting motor, viz by the mediation of a couplin which is temporaril elastic and couples t e motor with the s ewing lever during the throwing-on period. The

object proper of this arrangement is to obviate the special electromagnetic means hitherto employed for operating the slewing means for the pinion in question.

In order to make my invention more clear, I refer to the accompanying drawing, in which similar letters denote similar parts throughout the several views, and in which Fig. 1 is a: diagrammatical representation of the complete combination and arrangement of parts, the rotary parts being shown in axial direction. Fig. 2 is an axial section through these latter parts. Fig. 3 is an illustration similar to Fig. 2 showing a slightly modified form of construction. Fig. 4 is also an illustration similar to Fig. 2, or 3 respectively, and shows a third form of execution; this figure is drawn on a somewhat larger scale. Fig. 5 is an axial view of a detail of Fig. 4:.

Referring to Figs. 1 and 2, this is a form of construction in which the slewing of the coupling pinion is efiected by the rotary motion of the motor through the mediation of .an eddy-current coupling. a is the motor shaft, 1) a bearing cover, 1' a pinion keyed to said shaft, 8 an intermediate gear or coupling pinion which is rotatably supported on c a lever 0 by means of a bolt and meshes with the pinion 4', and t a gear connected to a power engine. This lever 0 may be slewed around the motor axle and is subjected to the action of a spring 9 which tends to pull I the lever back into the throwing-in position.

In Fig. 1 the lever c is shown as thrown on; the cog-wheels s and t mesh with each other, and the arm 72. which is rigidly connected with the lever o bears against the abutment .2. The slewable pinion s, after having been thrown on, is held fast in this position (Fig. 1) as long as the driving pinion r exerts a turning moment over the slewable pinion .9 upon the toothed rim t. To throw on the pin on s by the rotary motion of the starting motor, conformably with this invention, an eddy-current coupling is provided which consists of a pole core 6 attached to the lever c, a magnet coil f, and ametal disk d which is affixed to the motor shaft and rotates in front of the core 6. To throw on the eddycurrent coupling a current is made to pass through the coil 7 so that the disk at rotates m a strong magnetic field and exerts, .re-actmg, a turning moment upon the core a and the lever 0 by virtue of the eddy-currents induced in it. The lever is thus turned in the same direction as the disk 03, and the spring 9 is put under tension.

he succession of phases when throwing on the eddy-current coupling is as follows: When depressing the push-button 5 the current flows from the battery A over the contacts 2 and l which are bridged, in the position of rest of the gearing, by the contact le ver k,- then the current flows through the coil the motor M and then back to the battery. This makes the motor M start at the same time the pole core 6 is excited so that it, t ogether with the lever 0, is taken along by the eddy-current turning moment existing between the rotating disk d and the pole core e the slewable pinion .s' and the toothed rim which is to be driven are thus made to mesh with each other.

After the slewable pinion s has been thrown into gear with the toothed rim t, the switching lever is in a position in which it bridges the contacts 4 and 3. From this moment the current flows directly from the battery to the motor M and drives this with full power. Owing to the cog wheel re-action now arising the lever is further turned until the arm it meets the bolt i and the teeth of the wheels 8 and t are completely in gear with each other. Simultaneously the switching lever It leaves the segments 1 and 2 whereby the current throu h the magnet coil f is interrupted. The ed -current coupling is now released and the motor may transmit its full power to the toothed r1m t D' em t fthe inion to be dnven lsen ag en 0 P 'diskis .efi'ectedsby a spring p, whereas a s and the toothed T1111 t from one another takes place only when the power engine begins to operate under its own power, whereupon the tooth-reaction ceases, or reverses respectively, the lever 0 is released.and the 1 gears are thrown out of mesh by the spring The above-described arrangement makes use only of electromagnetic force fortsllevggj ing the lever 6, but it is as well use mechanical friction in lieu of-t e electromagnetic force whereby the effect may be in-v creased. For 'thatpurpose nothing, else is necessary but to make the disk d axially displaceable and to use magnetic 'material' for it so that it contacts with the. core-e when being attracted; by it and. transmits the necessary turning moment to the lever c by the friction between it and the core.

As the practical execution of the abovedescribed arrangement with its eddy-current coupling or friction coupling is connected with some difliculties, it is preferable to transmit the rotary; motion of the motor armature to the slewin lever in some other manner, for instance y the means illustrated in Fig. 3. Here an auxiliary pinionu is made use of, which is in permanent gear with the pinion r and is revolubly supported by the lever c and exerts a turmng moment upon it by impeding its rotary motion. The cog-wheel u is rotatably supported upon the core e of a pot-shaped magnet n which is directly connected with the lever c and has a hopper-shaped rim into which fits a correspondm ly shaped projection of the cog-wheel a. 5n exciting the cgil f the cog-wheel u is so powerfully attracted that owing to the conical pressure surfaces at, the hopper-shaped rim of the magnet and the proJection of the associate cog-wheel, a strong braking action arises whereby the lever c is slewed.

Anyhow, the magnetic pulling power requlred to produce the necessary friction is still retty great, but this state of things may e improved by directlyholding fast the pinion u by means of a pawl-like or claw-like coupling, perhaps of the kind illustrated in igs. 4 and 5, and by employing the ma et solely for actuating the pawl or claw. ut as it is necessary to make provision for thecase where the teeth of the wheels 8 and t-do not mesh with each other,

the coupling between the. lever and the' motor shaft must have a certain elasticity, that is to say, an elastic connection between the cog-wheel u and the coupling or pawl must be provided. Such an arrangement is illustrated in Figs. 4 and 5. The electromagnet 1i. this instance pot-shaped wheel a and a coupling disk Tlfeelastic.

connection-between the cog-wheel and thespring :vpres's'es thediskl outwards after it re'spondin y located recesses o o t e pot has been disengaged. -,On excitin the coil -f,--the disk Z is drawn againstt e pot'n 1 and suitabl provided lugs of it e a e corrim. where yfthe disk is prevented from rotatin upon the bolt e. ..Also the cog-wheel whic iselastically coupled. with Z by the -soturning moment u on the slewing lever is spring. p is held fast, w ereby the desired exerted. In case to gear wheels 8 and 't fail to 'mesh the slewing of the lever is delayed until, owing to the rotation of the cog-wheel u,'in connection with the tensioning of thes pring p, the wheel '8 meshes with the wheel t.

I claim: 4

1. In combination, an. electric starting motor for power engines, said motor having a shaft, a. pinionv on said motor shaft, an-.

engine gear, an intermediate gear actuated by. said pinion, a slewin lever for said intermediate gear, a mem r arranged for rotary motion, and an electromagnetic pawl device elastically connected with said shaft for checking the rotary motion of said member and therebycoupling said motor shaft to'said lever. Y 7 2. In combination an electric starting motor for power engines said motor having a shaft, a pinion on; said motor shaft, an engine gear, an intermediate gear actuated by said pinion, a slewing lever for said intermediate gear, an electromagnet for coupling said motor shaft to said lever, and a contact in the circuit of said electromagnet controlled by said lever, said contact being closed before, 'said' lever is slewed to energize said motor and bring the intermediate gear into mesh with said. engine gear and checking the rotary motion of said member' and thereby coupling said motor shaft to sand lever.

4. In combination, a source of power,

an electric starting motor for power engines. said motor having a'shaft, a pinion on said motor shaft, an engme gear, an inter mediate gear actuated by said motor, a slewing lever for said intermediate gear, an

electromagnet for coupling said motor shaft to said lever, a contact in the circuit of said tact adapted to be closed to directly conelectromagnet controlled by said lever, said nect said motor to said source when said contact being closed before said lever is intermediate gear is brought into mesh with 10 slewed to energize said motor and bring the said engine gear.

intermediate gear into mesh with said en In testlmony whereof I aflix my signagine gear, said contact being opened when ture.

said gears are in mesh, and a second con- HEINRICH BAUMEISTEB. 

